Multiple pig launching apparatus are commonly used for cleaning and inspecting pipelines. Since pipelines can collect water or other debris, a device called a “pig” can be introduced from a launcher into an upstream end of a pipeline. The launcher releases the pig and the fluid flow in the pipeline carries the pig and debris and/or liquids from the pipeline to a receiver or pig trap. The process of moving a pig through a pipeline is called pigging.
In pigging operations, a useful launching apparatus can operate automatically to regularly drop pigs. Reliability is very important considering the remote locations of these apparatus and the time and labor costs and operator risk to address malfunction.